This article explodes standard interpretations of the exclusionary rule, relying on archival sources to demonstrate that the Warren Court’s incorporation of the rule to the states did not professionalize police so much as worsen their conduct, increasing tensions between beat patrolmen and racial minorities. By the mid-sixties, such tensions escalated to the point that both white police and black activists derided the Court’s criminal procedure revolution as an effort not to ameliorate inequality so much as to contain the poor in urban ghettos. Rather than counter this charge, the Court proceeded to turn against urban protesters, upholding the convictions of a string of black demonstrators including national civil rights leaders like Martin Luther King, Jr. By 1968, such cases provided an odd corollary to the Court’s criminal procedure decisions, pointing to a little recognized drama of control aimed not at helping minorities so much as containing radical protest in the United States.